VALVE MAGAZINE Winter 2024

New Valve Modifications

By: GREG JOHNSON, President COMPANY: UNITED VALVE

Valve modification can be defined as: adding value to standard or “commodity” valves by installing actuators, special trims, different end-connections, packing and gaskets and other accessories or upgrades not provided on the original product. These modifications are primarily for gate, globe, check and ball valves. Back in the days of black and white television and cars with tailfins, end users usually had a storehouse full of valves commonly used in their plants. This was ideal for both the valve OEM and the distributor: everything was ordered in advance and the need for expedited-de livery, special valves was a random occurrence. However, belt-tightening measures by those end users lowered their inventories. Combined with the refinery and petro chemical construction boom of the 1970s, this created a situation where the supply capability of domestic manu facturers was exceeded for commodity and particularly for specialized valves. MODIFICATION BECOMES POPULAR Up until this time, modification of new valves by third party shops was only tacitly approved by a few OEMs. However, they soon began to see the advantages of authorizing quality valve service facilities to perform alter ations on their products. With an official authorization program, the OEM could retain oversight of the after market work performed on their products, plus reduce the number of bogus operations performed on their valves. This led to a system whereby individual manufacturers audited the facilities performing the modification work and only authorized those companies with the capabili ties and quality systems to perform the work correctly. Today, the OEM authorization system for gate, globe, check and ball valve modification is very strong, and widely used and accepted by OEMs, distributors and end users. However, modification of pressure relief valves almost exclusively consists of OEM parts replacement by an OEM and a national board-certified facility. The modi

fication of control valves is usually handled by an OEM’s own service centers. MSS MODIFICATION STANDARDS The Manufacturers Standardization Society (MSS) has accomplished a valuable service for the new valve modifi cation industry by creating a series of standard practices detailing how many popular valve modifications should be performed. The first MSS valve modification document, MSS SP-141, Multi-turn and Check Valve Modifications, was published in 2011. Here is the scope of that document: 1.1 This Standard Practice establishes minimum require ments for the modification of new gate, globe and check valves, which have been manufactured in accordance with recognized national standards and require modifi cation to meet specific end-user requirements. 1.2 The purpose of this Standard Practice is to ensure that the quality of workmanship and materials meet all applicable standards and codes. SP-141 contains basic instructions, welding criteria and non-destructive testing requirements for many modifica tions, including trim changes, changing ends from raised face to butt-weld ends, packing and gasket replacement, bypass installation and NACE International, MR01-03 compliance. The document also calls for OEM parts to be used if readily available. The following is verbiage from one of the nondestruc tive evaluation procedures contained in SP-141: dye pene trant (PT) examination. 10.2 Dye penetrant examination of valve body and bonnet 10.2.1 Scope—The procedure details the requirements for dye penetrant (PT) examination of bodies and bonnets of assembled valves, as per MSS SP-93 or ASME (American Society of Mechanical Engineers) B16.34. This procedure requires the replacement of the original packing and gasket.

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VALVE MAGAZINE

WINTER 2024